Idea for Desalination Facility Came Years Ago; Some Slam Its Cost, Energy Use

CARLSBAD, Calif.—When the San Diego County Water Authority first hatched a dream of slaking this region's thirst with desalinated water from the Pacific Ocean, Southern California was reeling from a five-year drought that had choked its water supply by a third.

That was two decades ago.

Now, after a yearslong permitting process, a spate of lawsuits and a complex coordination effort, that dream has resulted in a freshly poured...